In the standards organization 3GPP, studies are conducted for 3GPP RAN LTE (Long Term Evolution) to realize further improvement of present third mobile phone systems.
Presently in LTE standardization meetings, a synchronization channel (SCH) transmission method for detecting synchronization of an OFDM (Orthogonal Frequency Division Multiplexing) signal is discussed, and various methods are proposed for multiplexing a primary SCH (P-SCH) and a secondary SCH (S-SCH).
Non-Patent document 1 discloses one of P-SCH and S-SCH multiplexing method examples. The document discloses a P-SCH and S-SCH frequency division multiplexing method, in which P-SCHs are multiplexed subcarriers having lower frequencies and S-SCHs are multiplexed on subcarriers having higher frequencies, with respect to a DC subcarrier (see FIG. 1). To perform timing synchronization processing using a replica-based correlation method at the receiving side of the frame formed in this multiplexing method, only the P-SCH is extracted by a bandpass filter (BPF) and subjected to correlation calculation with a P-SCH replica, and symbol timing, subframe timing, and so on are detected from the timing a peak occurs.
Non-patent Document 1: NTT DoCoMo, et al, “SCH Structure and Cell Search Method for E-UTRA Downlink,” 3GPP TSG RAN WG1 Meeting *44 R1-060311